Outflow elements, or lower outlet pipes, are in part used to drain rain-water from flat roofs and typically into a sewer system.
Many of the outflow elements are fabricated from a lead plate within which a hole for the affixation of the end of a lead pipe has been made. By means of soldering or welding with the aid of lead, the pipe is sealed in a water-tight manner to the hole and the other end of the pipe is connected via an adapter to the drainage pipes, which drainage pipes are usually fabricated from PVC. Outflow elements having a single moulded lead entity are also known. Further, outflow elements made from other materials are known, such as those having a plate of the roof-covering material and a stainless steel outlet pipe, which plate and outlet pipe are sealed together in a mechanical manner. In general, the lead plate can be modified to the contours of the roof in situ by hand or with the use of light tools, and subsequently covered with a suitable roof-covering.
The known method suffers from the disadvantage, in particular in the in-situ situation where the outflow element is affixed to the roof, that it is laborious and furthermore requires the usage of heavy lead plates and tools which must be brought to the place of work in question and cut to size there. The prior making of one or more outflow elements in a workshop results later, as a consequence of the transport thereof, in a lack of roundness namely in the other extreme of the pipe, whereby the connection with the drainage pipes to the sewer leaves much to be desired, and this cannot be made air-tight and odour-tight without the use of extra means of assistance.
From the European patent application EP-A-502493 a device for floor drains is known. This device has a re-modellable plate with a hole, an outlet pipe and a clamping tube. The plate and the outlet pipe are first coupled during fabrication of the device by a clamping tube in the form of a round bar spring. This bar spring must be compressed before use and then positioned properly.